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OPS335 Lab 5

Revision as of 15:38, 29 March 2016 by Msaul (talk | contribs)

WEB SERVER RESOURCES

Online References:


OVERVIEW

In this lab, we will look at several separate technologies that are used with the Apache web server to install, configure and run web applications.

The basic purpose of the Apache web server is to serve text pages, images, and other static files. You can format those web-pages to appear nice, but they would lack dynamic functionality (i.e. the ability to change colors or font-size when the mouse moves over a link, button, etc). In other words using Apache web-server as a sole application would not make your web-pages more interesting.

If we want to add more features for our web-page (eg. dynamic functionality, security, e-commerce, etc), your webserver would need additional help. To provide additional help requires several resources - more than just the web server itself. A popular acronym to represent these foundations and servers is referred to as LAMP. It stands for Linux, Apache, MySQL, and PHP (or Python).

In this lab, we will set up one type of "LAMP solution" runs webmail (i.e. send and receive email in a web browser).


INVESTIGATION 1: SETTING UP A LAMP FOUNDATION

Linux Platform For Webserver (VM4)

First, create a new Linux VM that will be contained on the same subnet, using your existing DNS server (vm1), and firewall settings.

Perform the following steps:

  1. Create another virtual machine called vm4 from scratch (only a minimal setup is needed). If you forgot how to do this, refer to Lab1.

    For Interest: As an optional exercise: configure all your network settings (except the firewall) using the installation wizard during installation static IP
    (the address 192.168.X.5 should be available).

  2. Configure your vm4 virtual machine in the same way that you've configured the other three main VMs. This should be a quick exercise for you by now, including:
  • The Linux installation (minimum install)
  • If you didn't setup the network configuration during installation, make certain to connect to the correct network with a static IP
    (the address 192.168.X.5 should be available),
  • Making sure you're using your internal DNS server (make reference to vm4's IPADDR for domain resolution)
  • Configuring default rules for your iptables firewall (hint: use saved shell scripts)
  • Allowing passwordless login from the host's root account (for future backups)
  • Disabling selinux since you don't know how to configure it properly.

  1. Test your vm4 virtual machine to make certain that it functions correctly.


Apache

Second, install, configure and run the Apache webserver that will allow you to run a webmail application.

Perform the following steps:

  1. Install Apache (the package name is httpd), start the service, make it start automatically, and allow access to it through the firewall (Apache serves HTTP traffic which goes over TCP port 80).

Now if you navigate to vm4.youruserid.org in a web browser in your host - you should see an Apache testing page.

Delete the file /etc/httpd/conf.d/welcome.conf to get rid of the default page.

We're not going to have a lot of time to study various Apache options so we'll tell you what you're looking for but you have to find it yourself.

DocumentRoot specifies where Apache will look for documents to serve.

Now create the file index.html in your DocumentRoot directory with the following contents (replace the date with the current one):

Hello, this is a web page on vm4.yourid.org and the current time is Mar 28 22:16:27 EDT 2016!

If you refresh the page in Firefox - you should see the contents of your index.html. If you like - you can specify the filename index.html in the address but there's no need since it's a default.

It may seem obvious - but notice that the time doesn't change as you refresh the page.

PHP

We'll replace our index.html file with an index.php with the following contents:

Hello, this is a web page on vm4.yourid.org and the current time is <?php system("date"); ?>!

Notice that in a web browser the index.php file isn't treated as a default page and the contents don't contain the date, but instead have exactly the text above. That's because the PHP interpreter isn't installed by default on CentOS. Install it. The package comes with a working default Apache configuration so you don't need to enable it manually.

Refresh the page, notice that you now see the date instead of the call to the date command. This is a trivial example of dynamic web content - it doesn't need to be the same every time you look at it.

MySQL

MySQL is used to allow storage and retrieval of structured data. SQL is used by countless services for all kinds of use cases. Again we won't spend much time learning the details of MySQL configuration but you need a basic server set up. You may remember setting up MySQL from OPS235 - we're doing the nearly identical thing here.

Install MySQL. You may notice that it's actually called MariaDB now. They are two separate projects run by different groups but they are compatible so you can use documentation from one to configure the other. Make sure you have not just the client but also the server software.

When you start the service - you'll get some instructions in the log file about setting a root password. Even though we won't configure our service to be accessible over the network - you should get into the habit of doing this with every MySQL installation you ever make.

Note that MySQL has two root passwords - one for localhost and one for external requests. Just run the two commands you're given in the log. Use a password you make up yourself, but don't use a secret password - you'll be putting it in a plain text file later.

Roundcube Mail

We'll install Roundcube Mail. Download the tarball from their website directly into the html directory of your vm4 using wget. This part may take some effort depending on the Sourceforge website.

Extract the tarball and rename the directory to webmail.

In that directory there will be a file named INSTALL which will walk you through the rest of the installation.

Some notes:

  • Be careful about copy-pasting the MySQL setup part, don't try to rush it.
  • You'll need to install a couple more Apache modules: php-xml, php-pdo, and php-mysql.
  • Don't forget to set the password in the roundcube configuration.

Note that both your IMAP and SMTP servers are on different machines, not on vm4. For that to work you'll need to set the following options for Roundcube:

  • $config['smtp_server']
  • $config['default_host']
  • $config['default_port']

(the last two are your IMAP server). You should be able to test the configuration in your Roundcube installer Step 3.

COMPLETING THE LAB

Students should be prepared with all required commands (system information) displayed in a terminal (or multiple terminals) prior to calling the instructor for signoff.

Arrange evidence (command output) for each of these items on your screen, then ask your instructor to review them and sign off on the lab's completion:

Your webmail showing your inbox
Your webmail sending an email out
You receiving that mail on an exernal account